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Vehicle Sales Tax EngineRules engine
Demo · fictional data

A car is not taxed like a toaster.

Most ZIP-to-tax lookups stop at the general sales-tax rate. This engine goes one step further and applies each state's motor-vehicle rule: flat rates, caps, surtaxes that stop at $5,000, and states where tax isn't a percentage at all.

worksheet.keystone-auto.example/tax
Keystone Tax Enginedeal worksheet · sales tax
Demo subset with sample rates — the production engine covers every US ZIP. Local rates shown are samples, not current rates. Results are an illustrative estimate.

Deal inputs

Try:
  1. 1
    ZIP → state / county—offline lookup
  2. 2
    Combined sales-tax rate—general rate for the address
  3. 3
    Motor-vehicle rule—what actually applies to a car
  4. 4
    Final tax—illustrative estimate
Type a ZIP to run the engine.

Coverage demo subset

Rule + sample ZIPsNo sales taxManual rateProduction only

Sample ZIP table tap a row to load it

ZIPPlaceCombined (sample)Vehicle rule